首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
BACKGROUND: Increased incidence and prevalence of peripartum cardiomyopathy (PPCM) have been documented in the Hospital Albert Schweitzer (HAS) District of Haiti. Although the basis for this increased incidence of PPCM remains unclear, there is growing evidence for an underlying autoimmune process. One potential risk factor for increased autoreactivity is a micronutrient deficiency. In Africa, low plasma selenium (Se) level has been reported as a possible risk factor for PPCM. This report details results of initial studies to test the hypothesis that plasma levels of Se and/or other micronutrients may be related to PPCM risk in this population. METHODS: Under the direction of the Institutional Review Board (HAS Ethics Committee) and with informed consent, levels of Se and other micronutrients were measured in plasma samples obtained from PPCM mothers and parity-matched control mothers from the HAS District of Haiti. RESULTS: Mean plasma Se level in 18 PPCM patients was 110 ng/ml (range 67-145) compared to mean plasma Se level in 34 control mothers of 121 ng/ml (range 98-172) (P=0.1748). These levels are substantially greater than those reported for pediatric patients with Keshan cardiomyopathy, which can be prevented by Se prophylaxis. No deficiency or significant difference was found in any other micronutrient tested (Vitamin A (retinol), Vitamin B(12), Vitamin C, Vitamin E, and B-Carotene) for these PPCM and control mothers. CONCLUSION: Although there are several possible mechanisms by which Se could play a role in the pathobiology of PPCM, there is no evidence that Se deficiency is a cause of PPCM or a risk factor for the development of PPCM in this district of Haiti. The results of this investigation indicate that future studies of PPCM in this population should focus on other potential etiologic and risk factors.  相似文献   

2.
M Simi  S Leardi  M T Tebano  M Castelli  F M Costantini    V Speranza 《Gut》1987,28(3):336-338
Plasma platelet factor 4 (PF4), secreted by the platelets, is an index of platelet aggregation and thromboembolic risk. The authors assessed PF4 in 20 patients with Crohn's disease (ileitis in 13 patients, ileocolitis in seven) and in 20 healthy volunteers. Disease activity was low (Crohn's Disease Activity Index less than 150) in 11 patients and high in nine. Radioimmunoassay of PF4 using Abbott's Kit was performed on one sample of plasma from each subject (nv less than or equal to 0.324 nmol/ml), (nv less than or equal to 10 ng/ml). A significantly higher concentration of PF4 was found in Crohn's disease patients: 4.625 +/- 1.1 nmol/ml (142.5 +/- 36 ng/ml) than in the control group: 0.189 +/- 0.07 nmol/ml (5.6 +/- 4.8 ng/ml) (Z = 5.396, p less than 0.0001). No correlation was present between PF4 levels and activity, the site of disease, or medical treatment with or without prednisone.  相似文献   

3.
delta 5 and delta 4 steroid levels were studied in the plasma and cyst fluid of women with gross cystic breast disease (GCBD). In luteal phase a significant increase in plasma levels (mean +/- SEM) of DHA (11.2 +/- 2.4 ng/ml), DHAS (1.45 +/- 0.6 micrograms/ml) and cortisol 277 +/- 15.7 ng/ml) was found; in follicular phase the mean levels were 4.09 +/- 0.47 ng/ml for DHA, 0.65 +/- 0.08 microgram/ml for DHAS and 190 +/- 46.3 micrograms/ml for cortisol. The DHA/DHAS and cortisol/androstenedione ratios were significantly higher in the plasma and lower in the cyst fluid of GCBD patients, than in the plasma of controls; the androstenedione/DHA ratio was higher in the cyst fluid than in the plasma of controls. The hormonal situation of the GCBD patients thus differed from that of the controls both in the plasma and cyst fluid, particularly as regards the delta 5 steroids.  相似文献   

4.
Ascites and plasma concentrations of soluble tumor necrosis factor receptors p55 and p75 were measured in a prospective study in 34 patients (35 occasions of ascites) with hepatic (5 infected and 21 uninfected) and malignancy-related (9) ascites. All patients had high concentrations of both soluble tumor necrosis factor receptors in ascites and plasma; these were about 500 times higher than the corresponding tumor necrosis factor-alpha concentrations. Ascites levels of soluble tumor necrosis factor receptors p55 and soluble tumor necrosis factor receptors p75 were significantly elevated in patients with malignancy-related (p55: 26.0 +/- 8.6 ng/ml; p75: 20.5 +/- 17.4 ng/ml; mean +/- S.D.) and infected ascites (p55: 25.1 +/- 10.9 ng/ml, p75: 22.6 +/- 11.0 ng/ml) compared with patients with uncomplicated hepatic ascites (p55: 10.1 +/- 4.4 ng/ml; p75: 6.0 +/- 2.6 ng/ml). Patients with infected or malignancy-related ascites also showed higher soluble tumor necrosis factor receptor concentrations in plasma than did patients with plain hepatic ascites. Successful antibiotic treatment of peritonitis reduced soluble tumor necrosis factor receptor p55 and p75 ascites levels in three patients from 24.2 +/- 15.2 ng/ml to 10.7 +/- 1.9 ng/ml and from 20.2 +/- 14.4 ng/ml to 7.5 +/- 1.8 ng/ml, respectively. Soluble tumor necrosis factor receptors p55 and p75 at cutoff levels of 16.5 ng/ml and 9.5 ng/ml, respectively, differentiated between infected or malignant and plain hepatic ascites with diagnostic accuracies of 94% and 89%, respectively. They did not differentiate between infected and malignant ascites. The concentrations of soluble tumor necrosis factor receptor p55 were usually higher in ascites than in plasma in all subgroups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Using primed constant infusions of [14C]urea we assessed the effects in castrate male lambs of insulin-like growth factor (IGF) II infusion on protein metabolism during concurrent IGF-I infusion. A 300 minute infusion of IGF-I at 15 micrograms/kg.hour (n = 4) increased (p less than 0.001) the plasma IGF-I concentration from 72.5 +/- 6.4 ng/ml to 213.6 +/- 17.4 ng/ml and decreased (p less than 0.01) the rate of net protein catabolism (NPC) from 1.48 +/- 0.28 g/kg.day to 1.02 +/- 0.18 g/kg.day. Infusion of IGF-II at a dose of 50 micrograms/kg.hour concurrently with IGF-I at 15 micrograms/kg.hour (n = 4) was associated with a similar rise (p less than 0.01) in plasma IGF-I concentration from 79.4 +/- 4.1 ng/ml to 225.2 +/- 32.8 ng/ml. Plasma IGF-II increased (p less than 0.05) from 350.6 +/- 41.6 ng/ml to 746.7 +/- 165.5 ng/ml over the infusion. Coadministration of IGF-II completely blocked (p less than 0.01) the anabolic effect of IGF-I and the rate of NPC remained unchanged throughout the combined IGF-I and IGF-II infusion at a level comparable to saline infused controls (n = 4). This study suggests that IGF-II may play a physiological role as a circulating modulator of the anabolic effects of IGF-I.  相似文献   

6.
OBJECTIVE: Gastrointestinal angiodysplasia is a major cause of recurrent bleeding. Haemostatic abnormalities have been implicated in the haemorrhage from these common vascular lesions but their precise contribution remains to be established. Our aim was to investigate whether bleeding angiodysplasia is associated with any specific coagulation disorder. METHODS: Clinical features and blood samples were prospectively obtained from 21 patients with bleeding gastrointestinal angiodysplasia 3 months after the last episode of haemorrhage. Plasma levels of von Willebrand factor, D-dimer, plasminogen activator inhibitor type 1 (PAI-1), tissue-plasminogen activator activity, tissue factor pathway inhibitor and activated factor VII (FVIIa-rTF) were measured. A group of 14 patients with bleeding duodenal ulcer were similarly studied as controls. RESULTS: Mean plasma von Willebrand factor levels were higher in angiodysplasia patients (208+/-12%) than in controls (143+/-11%) (P<0.05). D-dimer levels (661+/-80 ng/ml) and tissue-plasminogen activator activity levels (2.04+/-0.14 IU/ml) were also higher than in controls: 395+/-99 ng/ml and 1.6+/-0.1 IU/ml, respectively (P<0.05), whereas levels of PAI-1, FVIIa-rTF and tissue factor pathway inhibitor were similar in both groups. However, PAI-1 levels (31.5+/-11 ng/ml) were lower in high-bleeding-rate angiodysplasia (more than two bleeding episodes/year) than in low-bleeding-rate angiodysplasia (< or = 2 bleeding episodes/year) (PAI-1 47+/-14 ng/ml) (P<0.05). In a multivariate regression analysis, the plasma level of PAI-1 was a predictor of haemorrhage from angiodysplasia (P<0.05). CONCLUSIONS: Increased plasma fibrinolytic activity may contribute to bleeding from angiodysplasia. Low plasma PAI-1 levels constitute a risk factor for bleeding tendency in patients with angiodysplasia.  相似文献   

7.
Although the mechanisms involved in the persistent clinical complications of sickle cell disease have not yet been fully delineated, previous studies suggest that sickle cell (HbSS) patients have a disposition to generate more thrombin and plasma in vivo than normal subjects. The reasons for the impaired regulation of haemostasis in HbSS patients is poorly understood. We report studies evaluating the extent to which in vivo coagulation and fibrinolysis are altered in HbSS patients in steady state. The concentrations of total factor VII (F(VII)t), factor VII zymogen (F(VII)z), thrombin-antithrombin III (TAT), fibrinopeptide A(FPA), and fibrin D-dimer in plasmas of 50 normal controls (HbAA) and 45 HbSS steady state patients, were measured using sensitive and specific enzyme-linked immunoassays. The average plasma concentration of F(VII)t, in sickle cell plasma was significantly lower than that of the control subjects (0.70 +/- 0.19 U/ml versus 1.16 +/- 0.41 U/ml), whereas F(VII)z in the patients and controls were 0.47 +/- 0.15 U/ml and 1.15 +/- 0.33 U/ml respectively, P < 0.001. Both measures of factor VII suggest a higher factor VII turnover in sickle cell disease. The mean concentration of TAT in the plasma of HbSS patients were significantly higher than those of HbAA controls (371 +/- 44 pM versus 42 +/- 2 pM) (P < 0.001), a difference that is strongly indicative of higher rates of in vivo thrombin generation by HbSS patients. Plasmas of HbSS patients had significantly higher concentrations of FPA compared to those of the control subjects (12.85 +/- 1.96 ng/ml versus 4.22 +/- 0.37 ng/ml) (P < 0.001). The D-dimer levels were also higher in the HbSS than control plasmas (1029.6 +/- 58.6 ng/ml versus 224.3 +/- 27.6 g/ml) (P < 0.001), with the patients' values being indicative of enhanced fibrinolysis. These results strongly suggest accelerated in vivo coagulation and fibrinolysis in HbSS patients even during steady state. They are consistent with the hypothesis that haemostasis is less tightly regulated in the HbSS patients than in HbAA controls. The altered regulation of haemostasis may contribute to the initiation of vaso-occlusive processes associated with sickle cell painful episodes.  相似文献   

8.
BACKGROUND: According to previous reports, plasma atrial natriuretic peptide levels increase in atrial fibrillation (AF) and decrease after successful direct current (DC) cardioversion, but there have been no reports on plasma brain natriuretic peptide (BNP). OBJECTIVE: To determine whether plasma BNP levels decrease after successful direct DC cardioversion in patients with chronic AF. PATIENTS AND METHODS: Twenty patients who remained in sinus rhythm for at least seven days after cardioversion, and 20 normal control subjects, were studied. Group A consisted of 10 patients with underlying heart disease, including dilated cardiomyopathy (n=2), hypertrophic cardiomyopathy (n=1), mitral valve disease (n=3), hypertensive heart disease (n=3) and status after atrial septal closure (n=1). Group B consisted of 10 patients with just AF. Group C (serving as controls) comprised 20 subjects with normal sinus rhythm and no risk factors. RESULTS: Before cardioversion, plasma BNP levels were higher in group A (176.7+/-128.1 ng/mL) and in group B (96.8+/-51.7 ng/ml) than in group C (6.3+/-3.8 ng/ml) (P<0.01 for all). After successful cardioversion, mean plasma BNP levels in groups A and B decreased from 136.8+/-105.5 ng/mL to 46.4+/-44.2 ng/mL (P<0.01). In group A, plasma BNP levels decreased from 176.7+/-128.1 ng/mL to 62.5+/-54.6 ng/mL (P<0.01), and in group B, plasma BNP levels decreased from 96.8+/-51.7 ng/mL to 30.3+/-23.8 ng/mL (P<0.01). CONCLUSIONS: Lone AF raises plasma BNP levels, which is more marked if there is underlying structural heart disease present, and cardioversion reduces plasma BNP levels. Therefore, high plasma BNP levels in patients with chronic AF are likely to be caused by AF and reflect cardiac overloading associated with, although contributed to in part by, underlying heart diseases.  相似文献   

9.
BACKGROUND AND AIM: Pakistani people belong to an ethnic group which has the highest rate of coronary artery disease (CAD). We investigated the possible correlation between deficiency of vitamins B6, B12 or folic acid and hyperhomocysteinemia in Pakistani patients with acute myocardial infarction (AMI). A case-control study was carried out involving 224 AMI patients (age 30-70 years; 55 females and 169 males) and 126 normal healthy subjects (age 31-70 years; 35 females and 91 males). METHODS AND RESULTS: Fasting venous blood was obtained from cases and controls. Serum was analyzed for folic acid and B12 using radioassays. Plasma was analyzed for pyridoxal phosphate (PLP; coenzymic form of B6) using a radioenzymatic assay and for total homocysteine using a fluorescence polarization immunoassay. Mean serum B12 concentration in AMI patients was found to be significantly lower than the mean for controls (241+/-185 pg/ml vs 608+/-341 pg/ml; p < 0.001). Mean serum folate level in patients was also found to be lower than controls (3.35+/-3.78 ng/ml vs 4.93+/-2.93 ng/ml), however, the differences were not statistically significant. Similarly, mean PLP concentration in plasma of cases (19.4+/-24.4 nmol/l) was lower than the concentration in controls (23.2+/-17.6 nmol/l), but the difference was not statistically significant. Mean plasma homocysteine level in AMI cases (18+/-8.36 micromol/l) was higher than the mean level in controls (16.4+/-4.9 micromol/l), but not to a significant extent. However, this mean homocysteine concentration in normal healthy subjects was among the highest reported in the literature and was significantly more than mean values reported in most Eastern and Western studies. Compared to controls, there was significantly greater deficiency of folate (32.5% vs 67.1%), B12 (3.2% vs 63.4%) and PLP (49.2% vs 74.1%) in AMI patients. Deficiencies of folate, B12 and PLP were defined as serum folate levels less than 3.5 ng/ml, serum levels of B12 less than 200 pg/ml and plasma PLP levels less than 20 nmol/l. Mean plasma homocysteine levels in smokers were found to be significantly higher in both cases and controls. Similarly, mean serum folate levels in smokers (compared to nonsmokers) were significantly lower in both cases and controls. CONCLUSIONS: Substantial nutritional deficiencies of these three vitamins along with mild hyperhomocysteinemia, perhaps through an interplay with the classical cardiovascular risk factors (highly prevalent in this population), could be further aggravating the risk of CAD in the Pakistani population.  相似文献   

10.
A simple method for measuring the free, non-protein-bound steroid fraction in plasma by equilibrium dialysis is described. The alteration occurring in the volume of the inner phase (undiluted plasma) is corrected by the difference in weight before and after dialysis. Total cortisol was determined by radioimmunoassay. Although it is not possible to differentiate between values for total cortisol after ACTH stimulation (242.2+/-shing's syndrome (n: 15)), and women treated with oestrogens (211.8+/-42.0 ng/ml (n: 20)), there were significant differences for free cortisol (ACTH stimulation: 29.3+/-5.6 ng/ml; Cushing's syndrome: 31.5+/-8.6 ng/ml; women under increased oestrogenic activity: 10.0+/-2.1 ng/ml; pregnant women: 13.7+/-5.1 ng/ml plasma). Compared with normal values for healthy women and men (9.3+/-1.4 ng/ml), women with increased oestrogenic activity showed slight elevations of free cortisol. Compared to cortisol, the percentage of dialysable testosterone and oestradiol was lower in women than in men (1.57 vs. 2.08% for testosterone and 1.68 vs. 2.15% for oestradiol). In healthy men the concentration of free steroid was 13.1+/-1.0 ng free testosterone/100 ml plasma (0.44+/-0.045 pg free oestradiol/ml plasma), in healthy women 0.64+/-0.07 ng/100 ml (0.98+/-0.10 pg/ml) and in women receiving oestrogens 0.37+/-0.04 ng/100 ml (0.01+/-0.015 pg/ml). When the method described here for determing the free fractions of cortisol (n: 45), oestradiol (n: 18) and testosterone (n: 18) at 37 degrees C is compared with the method of centrifugal filtration, the correlation was r: 0.80 r: 0.86 and r: 0.91, respectively. In practice, equilibrium dialysis with undiluted plasma is simple, fast and can be applied to all steroid hormones. It allows direct measurements of non-protein-bound steroids under nearly physiological conditions.  相似文献   

11.
Intravenous immune globulin in the therapy of peripartum cardiomyopathy.   总被引:5,自引:0,他引:5  
OBJECTIVES: We sought to evaluate the effect of therapy with intravenous immune globulin on recovery of left ventricular function in women presenting with peripartum cardiomyopathy. BACKGROUND: Peripartum cardiomyopathy is a rare complication of pregnancy that results in significant morbidity and mortality in women of childbearing age. Intravenous immune globulin has been reported to improve left ventricular systolic function in patients with acute dilated cardiomyopathy and myocarditis, but its effectiveness in peripartum cardiomyopathy is unknown. METHODS: In this retrospective study, we compared the clinical outcomes of six women with peripartum cardiomyopathy treated with intravenous immune globulin (2 g/kg) with those of 11 recent historical control subjects. All women in the study were referred between 1991 and 1998 with class II to IV heart failure and a left ventricular ejection fraction of <0.40. Left ventricular ejection was reassessed during early follow-up (6.1+/-2.9 months). RESULTS: The two groups did not differ in terms of baseline left ventricular ejection fraction, left ventricular end-diastolic diameter, months to presentation, age or multiparity. The improvement in left ventricular ejection fraction in patients treated with immune globulin was significantly greater than in the conventionally treated group (increase of 26+/-8 ejection fraction units vs. 13+/-13, p = 0.042). CONCLUSIONS: In this small retrospective study of women with peripartum cardiomyopathy, patients treated with immune globulin had a greater improvement in ejection fraction during early follow-up than patients treated conventionally. Given the poor prognosis of women with peripartum cardiomyopathy who do not improve, this therapy merits further study.  相似文献   

12.
To evaluate the prognosis of patients with idiopathic dilated cardiomyopathy (EF less than 50%) in 55 patients the myocardial catecholamine concentration, plasma catecholamine concentration, and left ventricular ejection fraction were determined. The follow-up time ranged from 7 to 47 months. At the time of follow-up 10 of the 55 patients (group A) had died and three had undergone hearttransplantation. Group A patients had a significant lower EF (27 +/- 10 vs 36 +/- 9%, p less than 0.03), a lower myocardial norepinephrine (254 +/- 168 vs 579 +/- 416 pg/mg, p less than 0.007), higher plasma norepinephrine (640 +/- 333 vs 372 +/- 254 pg/ml, p less than 0.008) and plasma epinephrine (391 +/- 340 vs 116 +/- 81 pg/ml, p less than 0.006) in comparison to patients, who were still alive and not transplanted (group B). Survival was significantly lower in patients with an EF less than 30%, a plasma norepinephrine concentration greater than 350 pg/ml, a plasma epinephrine concentration greater than 125 pg/ml, and a myocardial norepinephrine content less than 400 pg/mg. Cox regression analysis revealed that the ratio of plasma vs myocardial norepinephrine was the best prognostic indicator for patients with an EF less than 30% and this ratio plus the plasma norepinephrine concentration were the best prognostic indicators for the whole group of patients. These data suggest that myocardial norepinephrine content is an important prognostic factor in patients with idiopathic dilated cardiomyopathy.  相似文献   

13.
BACKGROUND: Elevated total plasma homocysteine (tHcy) levels are considered a risk factor for cerebrovascular disease and may also play an important role in the pathogenesis of Alzheimer's disease (AD). High values of plasma tHcy and low levels of vitamin B(12) and folate are frequently present in AD patients. Moreover, the homozygous mutation (C677T) of the methylene tetrahydrofolate reductase (MTHFR) gene, related to a thermolabile type of the encoded enzyme, causes hyperhomocysteinemia by reducing the 5-methyltetrahydrofolate availability. OBJECTIVE: The aim of the study was to investigate plasma levels of folate, vitamin B(12) and tHcy in patients with AD. These values were also related to the severity and the duration of the disease and to the possible role of the MTHFR genotype (C677T). METHOD: Plasma tHcy levels, homozygosity for the C677T mutation of the MTHFR gene, and folate and vitamin B(12) plasma levels were evaluated in 74 patients with AD (45 men, 29 women, mean age 68 years) and in 74 healthy matched controls (42 men, 32 women, mean age 68 years). RESULTS: AD patients had higher mean (+/- SD) plasma levels of tHcy (20.9 +/- 15 micromol/l compared to 11.8 +/- 5 micromol/l, p < 0.001) and lower mean plasma folate (5.7 +/- 2.1 ng/ml compared to 8.5 +/- 3.2 ng/ml, p < 0.001) and vitamin B(12) (491 +/- 144 pmol/l compared to 780 +/- 211 pmol/l, p < 0.001) concentrations. Homozygosity for the C677T mutation of the MTHFR gene had a similar prevalence among controls (18%) and AD patients (20%). Homozygous AD patients (n = 15) had higher plasma tHcy values than nonhomozygotes, in spite of similar mean plasma folate and vitamin B(12) levels. This difference in plasma tHcy levels was not observed in controls. Patients with levels of plasma tHcy above and of plasma folate below the normal limits were more frequent in the homozygous AD group. The duration of the disease correlated with plasma levels of tHcy (r = +0.832, p < 0.001), plasma folate (r = -0.580, p < 0.05), and vitamin B(12) (r = -0.460, p < 0.05). However, when all the data were corrected for age, serum creatinine levels, and duration of the disease, mean plasma tHcy, folate, and vitamin B(12) levels were not statistically different between controls and AD patients. CONCLUSIONS: Our data suggest that rather than a risk factor for AD, hyperhomocysteinemia is related to its progression and increasing severity. This might be particularly relevant in homozygotes for the C677T mutation of the MTHFR gene and supports the possible need for continuous supplements in this setting.  相似文献   

14.
Selenium deficiency has been implicated as contributing to the development of cardiovascular disease, skeletal muscle myopathy, anemia, increased cancer risk, and deranged immune function. Since these problems may also be associated with renal failure, and the kidney plays an important role in selenium homeostasis, we measured selenium and compared it with nutritional status in 24 stable hemodialysis patients, 12 chronic intermittent peritoneal dialysis patients, and 29 healthy controls. Whole blood and plasma selenium was determined by a spectrofluorometric method. For whole blood the mean (+/- SD) selenium levels were 0.11 +/- 0.02 micrograms/ml in controls vs. 0.071 +/- 0.01 micrograms/ml in hemodialysis cases and 0.052 +/- 0.006 micrograms/ml in peritoneal dialysis (p less than 0.005). Significant decreases were seen also for plasma and red blood cell selenium in all groups respectively. Pre- and postdialysis plasma and whole blood selenium levels showed no significant changes in both dialysis groups. However, predialysis residual peritoneal fluid did contain selenium (0.029 +/- 0.005 micrograms/ml). Some evidence of protein-energy undernutrition was noted in both dialysis groups compared with controls. However, no significant differences in nutritional parameters were noted between hemodialysis and peritoneal dialysis patients. When all groups were combined, significant correlations were found between whole blood selenium and serum albumin (r = 0.61; p less than 0.001), triceps skin fold in females (r = 0.62; p less than 0.001), and midarm muscle circumference in males (r = 0.71; p less than 0.001). We conclude that low blood selenium is present in renal failure patients undergoing hemodialysis. This abnormality is even greater in peritoneal dialysis cases.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
BACKGROUND. This study evaluated the role of changes in heart rate, atrial pressure, volume, and cardiac tissue atrial natriuretic factor (ANF) concentration in the modulation of plasma ANF concentration in a model of pacing-induced heart failure. METHODS AND RESULTS. The effects of acute right ventricular pacing (250 beats/min), acute volume expansion (35 ml/min), and volume expansion after 1 week of right ventricular pacing on plasma ANF concentration were compared in eight dogs (group 1). As shown during right ventricular pacing previously, volume expansion produced significant increases in cardiac filling pressures and left atrial volume. Right ventricular pacing and volume expansion produced similar increments in plasma ANF concentration: from 32 +/- 12 to 168 +/- 153 pg/ml (p less than 0.05) and from 32 +/- 9 to 137 +/- 113 pg/ml (p less than 0.05), respectively. When pacing was initiated after volume expansion, plasma ANF concentration increased further to 462 +/- 295 pg/ml (p less than 0.05) despite little change in filling pressures and left atrial volume. With repeated volume expansion after 1 week of pacing, there were no significant further increases in left atrial volume and plasma ANF concentrations (from 332 +/- 121 to 407 +/- 113 pg/ml) despite significant increases in filling pressures. Atrial and ventricular tissue samples were also obtained from 21 dogs paced to severe heart failure (group 2) and from 14 normal dogs (controls). In all groups, atrial ANF was higher than ventricular ANF concentration. At 1 week (group 1), left atrial appendage ANF concentration (6.2 +/- 2.5 versus 16.1 +/- 10.3 ng/mg) was reduced, whereas left ventricular free wall ANF concentration (0.62 +/- 0.31 versus 0.24 +/- 0.16 pg/mg) was increased compared with that of controls (both p less than 0.001). At severe heart failure (group 2), atrial ANF remained low, whereas ventricular ANF concentration was similar to that of the controls. CONCLUSIONS. These data indicate that in pacing-induced heart failure, changes in heart rate, atrial pressure, and volume all contribute to the increased plasma ANF concentration. However, by 1 week (early heart failure), ANF release is attenuated, perhaps because of the inability of the atria to be stretched further and because of reduced atrial ANF concentration. In addition, the ventricle may be an additional source of ANF.  相似文献   

16.
Context: Pregnant tissues express corticotropin-releasing factor (CRF), a peptide modulating fetal and placental ACTH and cortisol secretion. These actions are modulated by the locally expressed CRF-binding protein (CRF-BP). Objective: The objective of the study was to determine whether CRF, CRF-BP, ACTH, and cortisol concentrations change in amniotic fluid and umbilical cord plasma in the presence of intraamniotic infection/inflammation (IAI) in women with spontaneous labor at term. Design: This was a cross-sectional study. Setting: The study was conducted at a tertiary referral center for obstetric care. Patients: Patients included women in active labor at term with (n = 39) and without (controls; n = 78) IAI. Main Outcome Measures: Amniotic fluid and umbilical cord plasma concentrations of CRF, CRF-BP, ACTH, and cortisol measured by RIA and immunoradiometric assays were measured. Results: In patients with IAI, amniotic fluid CRF (0.97 +/- 0.18 ng/ml) and CRF-BP (33.06 +/- 5.54 nmol/liter) concentrations were significantly (P < 0.001) higher than in controls (CRF: 0.32 +/- 0.04 ng/ml; CRF-BP: 14.69 +/- 2.79 ml). The umbilical cord plasma CRF and CRF-BP concentrations were significantly (P < 0.001 for all) higher in women with IAI than in controls (CRF: 2.96 +/- 0.35 ng/ml vs. 0.38 +/- 0.18 ng/ml; CRF-BP: 152.12 +/- 5.94 nmol/liter vs. 106.9 +/- 5.97 nmol/liter). In contrast, amniotic fluid and umbilical cord plasma ACTH and cortisol concentrations did not differ between groups. Conclusions: Amniotic fluid and umbilical cord plasma CRF and CRF-BP concentrations are increased in women with spontaneous labor at term and IAI. CRF-BP may modulate CRF actions on ACTH and cortisol secretion, playing a pivotal role in limiting the inflammatory process and thus avoiding an overactivation of the fetal/placental hypothalamus-pituitary-adrenal axis at birth.  相似文献   

17.
BACKGROUND: The myeloid-related protein complex (MRP8/14) is expressed in activated human macrophages and reported to be involved in the inflammatory process. The expression of MRP8/14 in patients with cardiac sarcoidosis and idiopathic dilated cardiomyopathy (DCM) was investigated. METHODS AND RESULTS: Serum MRP8/14 levels were measured in 35 patients with sarcoidosis and 23 patients with DCM. Sera from 30 normal volunteers served as controls. Additionally, the expression profiles of MRP8/14 in the myocardium from 12 patients with active cardiac sarcoidosis and 10 DCM patients were examined immunohistochemically. Serum MRP8/14 levels were significantly higher in patients with sarcoidosis than in normal controls [515+/-549 (SD) ng/ml vs 230+/-115 ng/ml, p=0.0019]. In the sarcoidosis group, serum MRP8/14 levels in patients with definite cardiac involvement (n=10) were significantly higher than in those without (n=25) (974+/-878 ng/ml vs 332+/-204 ng/ml, p=0.0227) and they were also higher than in DCM patients (vs 252+/-108 ng/ml, p=0.0026). Immunohistochemically, MRP8/14 was specifically positive in the cytoplasm of macrophages and multinucleated giant cells in the myocardial granulomas. CONCLUSIONS: MRP8/14 may be involved in the pathogenesis of sarcoid granulomas. The measurement of serum MRP8/14 levels is useful for the diagnosis of sarcoidosis, and their higher levels suggest the cardiac involvement.  相似文献   

18.
Carbohydrate intolerance is frequently seen in patients with hepatic cirrhosis. To study the role of the counter regulatory hormones, glucagon, cortisol and growth hormone in this disease, these hormones were measured in 11 patients with hepatic cirrhosis and six controls during a 4-hour oral glucose tolerance test (OGTT) and in five normal and cirrhotic subjects during steady-state plasma insulin and glucose concentrations (SSPGI) achieved with the euglycemic clamp technique. Fasting plasma glucose was 103 +/- 4.3 mg/dl in cirrhotics and 88 +/- 3.3 mg/dl in controls (p less than 0.001). Immunoreactive insulin (IRI) was 24.3 microU/ml in cirrhotics and 12.7 +/- 2.2 microU/ml in controls (p less than 0.001); immunoreactive glucagon (IRG) was 263 +/- 30 pg/ml in cirrhotics and 122 +/- 17.5 pg/ml in controls (p less than 0.001); serum growth hormone (GH) was 4.4 +/- 0.9 ng/ml in cirrhotics and 0.5 +/- 0.1 ng/ml in controls (p less than 0.001). During OGTT, the 2-hour glucose concentration was 201 +/- 9.7 mg/dl in cirrhotic subjects and 147 +/- 10.0 mg/dl in controls (p less than 0.001). IRG levels were suppressed by 20% of basal values in patients with cirrhosis, while controls showed 10% suppression after an oral glucose load. At 60 minutes, the serum GH was 14.7 +/- 3.9 ng/ml in cirrhotics and 0.3 +/- 0.1 ng/ml in controls (p less than 0.001). The normal suppressive effect of hyperglycemia on GH secretion in controls was sharply contrasted by a paradoxical elevation of serum GH in the cirrhotic group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Tissue factor (TF) is one of the major initiators of coagulation and raised plasma levels have been found in various cardiovascular diseases. TF activity is, however, regulated by tissue factor pathway inhibitor (TFPI), and alteration in levels of TF and/or TFPI may thus relate to thrombogenesis and atherogenesis. To investigate possible abnormalities in TF and free TFPI (i.e. unbound to TF) and total TFPI among patients with peripheral artery disease (PAD), we studied 42 patients (mean age 57, 35 men) with objectively proven (by ABPI/Doppler) disease and 42 age- and sex- matched healthy controls. TF, free TFPI and total TFPI were measured in citrated plasma by ELISA. TF was higher in the patients with PAD compared to controls (275+/-122 pg/ml versus 158+/-60, P<0.0001) but levels of total TFPI were lower in the patients (43+/-10 ng/ml versus 50+/-15, P=0.021). There was no significant difference in levels of free TFPI between patients and controls (7.2+/-1.5 ng/ml in controls, 7.5+/-1. 6 among patients, P=0.39). Within the control patients, levels of free and total TFPI were significantly correlated (Spearman r=0.51, P=0.001) but in the patients with PAD this correlation was poor (r=0. 21, P=0.178). We suggest that reduced levels of total TFPI and raised levels of TF may contribute to the process of atherogenesis and the increased risk of thrombosis among patients with cardiovascular disease.  相似文献   

20.
We infused intravenously recombinant human Insulin-like Growth Factor-I (IGF-I; 1 microgram/kg/min for 120 minutes after an acute dose of 25 micrograms/kg) into chronically catheterized ovine fetuses (124-132 days gestation) to study its effect on the secretion of fetal ovine Growth Hormone (oGH). In all IGF-I infused fetuses, oGH concentrations fell during the infusion. The maximal change in the concentration of oGH (mean +/- SEM) was -54 +/- 10 ng/ml in contrast to +7 +/- 6 ng/ml in saline controls (p less than 0.005), a decrease of 33 +/- 4% (controls: +6 +/- 5%; p less than 0.005). By 60 minutes after the infusion of IGF-I was completed, the concentration of plasma oGH was comparable to control and pre-infusion values. In IGF-I infused fetuses, the mean concentration of insulin also decreased (p less than 0.02), whereas glucose levels remained unaltered. The results suggest that the lack of inhibitory feedback by the relatively low levels of circulating IGF-I is one factor in the hypersecretion of GH by the fetus.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号